Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1992-3-31
pubmed:abstractText
Leaf thionins of several barley cultivars and wild barley species were analysed. We found large differences in the numbers of leaf thionin genes in different Hordeum species. While, for instance, cultivars of Hordeum vulgare (Section Hordeum) contain more than 50 copies of thionin genes per haploid genome, the numbers are much lower in Hordeum species belonging to the sections Critesion and Stenostachys. The apparent number of genes correlates with the concentration of leaf thionin and its mRNA, which differs more than 100-fold among various Hordeum species. Leaf thionins are synthesized as high molecular weight precursor proteins that contain a signal peptide domain, a thionin domain and an acidic polypeptide domain. Analysis of cDNA clones of leaf thionins revealed a family of related transcripts. When the predicted amino acid sequences of the precursor molecules of wild barley species were compared, differences in the sequence variability of the three domains became apparent. The frequency of amino acid exchanges is much higher within the thionin domain than in the signal peptide and acidic polypeptide domains. The amino acid exchanges within the thionin domain do not occur at random but are confined to variable regions that alternate with highly conserved areas. Conserved regions comprise mostly cysteine residues and adjacent amino acids and may be important for the correct formation of the specific disulphide configuration of thionins.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0026-8925
pubmed:author
pubmed:issnType
Print
pubmed:volume
231
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
460-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
A comparison of leaf thionin sequences of barley cultivars and wild barley species.
pubmed:affiliation
Botanisches Institut der Christian-Albrechts-Universität Kiel, FRG.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't